Manufacture of detergents



Feb. 12, 11946.. L. H. ,FLETT 2,394,851

MANUFACTURE OF DETERGENTS 4 I Fild Aug. 12,1941

CHLORINA T50 PTROLEUM DIST/L LATE- All? BATH I PETROLEUM -7 DISTILLATE Z v w 6 i CHLDRINE INVENTOR LAWRENCE H. FLETT Patented Feb. 12, 1946 2,394,851 MANUFACTURE OF DETERGENTS Lawrence H. Flett, Hamburg, N. Y., assignor to Allied Chemical & Dye Corporation, a corporation of New York Application August 12, 1941, Serial No. 406,553

6 Claims.

This invention relates to improvements in the manufacture of detergents and related compositions comprising mixtures of sulfonated nuclearly substituted aromatic hydrocarbons containing not more than two benzene nuclei in the aromatic nucleus, in which the nuclear substituents are derived from complex hydrocarbon mixtures of mineral origin, as for example, crude petroleum, and preferably petroleum fractions comprising not more than 20 per cent of aryl compounds. It relates more particularly to improvements in the process of producing such nuclearly substituted aromatic sulfonates which involves condensing a kerosene fraction of a petroleum distillate with a benzene hydrocarbon,

such as benzene, toluene, etc., and sulfonating resulting mixed nuclearly substituted benzene.

compounds. (As employed herein, the term mixed, when applied to nuclearly substituted benzene compounds, aromatic compounds, aromatic sulfonates, and related substances, denotes mixtures of such substances.) It relates especially to a method of preparing the mixed nuclearly substituted aromatic compounds for sulfonation so that upon sulfonation, followed by conversion of the sulfonation product to salts and drying, mixed nuclearly substituted aromatic sulfonates are obtained which have improved properties.- (Since the nuclear substitu'ents are derived from complex hydrocarbon mixtures of mineral origin, and accordingly are to a considerable extent aliphatic acyclic and alicyclic in nature, the nuclearly substituted aromatic sulfonates have come to be known in the art as alkyl aromatic sulfonates,- the term alkyl being used in a generic sense to denote a nuclear substituent radical derived from the hydrocarbon mixture. Accordingly the nuclearly substituted aromatic compounds will be referred to herein as alkyl aromatic compounds and the term alkyr will be employed in said generic sense.)

An object of the present invention is to provide improvements in the manufacture of mixed higher alkyl aromatic sulfonates of the said type from complex hydrocarbon mixtures of mineral v origin, whereby products having improved properties are obtained.

'Another object of the present invention is to provide improvements in the method of producing higher alkyl benzene sulfonates from chlorinated kerosene fractions of petroleum distillates and benzene hydrocarbons by condensation with the aid of a Friedel and Crafts condensing agent,

particularly aluminum chloride as a condensetion catalyst, followed by sulfonation, whereby sulfonated products are obtained having improved properties, particularly with respect to odor and stability on standing of their aqueous solutions.

Other objects of the invention in part will be obvious and in part will appear hereinafter.

The mixed alkyl aromatic sulfonates with which the present invention is concerned are preferably. derivatives of aromatic compounds of major portion of the organic sulfonates are compounds defined by the following formula:

q R-A-SOaY in which A represents a mononuclear .or dinuclear aromatic hydrocarbon residue, such as the nucleus of benzene, naphthalene or diphenyl, but preferably of benzene; X'represents a replaceable hydrogen or a lower alkyl group attached to a nuclear carbon atom of the aryl residue;

preferably X represents replaceable hydrogen but in case X represents an alkyl group, u may be 1, 2, or 3, preferably 11. is canal to l; SOsY repre-,

sents an unneutralized sulfo group which is attached to carbon of the aryl nucleus and in which Y may be replaced to form salts of the acid by a salt-forming metal or radical, such as sodium, potassium, ammonium, alkyl ammonium, hydroxy alkyl ammonium, etc., but preferably sodium; and R represents a substituent group derivable from a petroleum fraction in which the hydrocarbons contain at least '1 and not more than 35 carbon atoms per molecule, and preferably an average of 10 to 16 carbon atoms per molecule. Thus the products may be derivatives of benzene, naphthalene, diphenyl, and their homologs.

Mixtures of 'sulfonated higher alkyl derivativesof aromatic hydrocarbons in which the alkyl groups are derived from complex hydrocarbon mixtures of mineral origin represent a desirable class of products, particularly in the form of their alkali metal and organic amine salts, for use as substitutes for soaps and as surface active agents in view of certain of their advantageous properties; as, for example, resistance to acid and hard water, washing and lathering ability in hard water and sea water, and freedom. from hydrolysis.

As pointed out above, the alkyl groups or sidechains present in the sulfonates are derived from a hydrocarbon mixture of the type of a petroleum distillate; for example, a kerosene fraction or a white oil" fraction of petroleum, and preferably a parafllnic petroleum hydrocarbon distillate. The hydrocarbon fraction from which the alkyl group is to be derived is generally chlorinated to increase its chemical reactivity.

According to the usual procedure for making mixed alkyl aromatic compounds, a Friedel and Crafts type of condensation is carried out with the aid of anhydrous aluminum chloride as the condensing agent and the non-tarry portion of the reaction mass is separated by decantation or other mechanical means from the tarry by-products formed during the condensation reaction. The crude, non-tarry product is a mixture of the products of the condensation and uncondensed low-boiling materials, such as the aromatic and aliphatic hydrocarbons. The crude product may be stripped of the lower boiling aromatic and aliphatic compounds by distillation and the remainder, containing the desired alkyl aromatic compounds, may be sulfonated to obtain a valuable detergent mixture; it is preferable, however, to divide the crude product by distillation into fractions. In the preferred procedure, the crude product is distilled into four distinct fractions as follows: Fraction #1.A low-boiling distillate which is chiefly unreacted material, mostly the aromatic compound (e. g. benzol, etc.) which was charged to the condensation but which remained unaffected by the Friedel-Crafts condensation reaction. This fraction also contains other low-boiling hydrocarbons and chlorinated compounds.

Fraction #2.An intermediate distillate following Fraction #1 and consisting chiefly of monoalkyl aromatic compounds containing an average of one alkyl group for each aromatic molecule, which is preferably subjected to sulfonation 'for the production of detergents and surface-active agents,

Fraction #3.-A high-boiling distillate which follows Fraction #2 and probably consists of poly- In the preparation of alkyl aromatic compounds by condensing a mixture of alkyl chlorides, such as chlorinated kerosene or a chlorination product of a higher petroleum distillate, such as those mentioned above, with an aromatic hydrocarbon. such as benzene, the reactants are ordinarily brought together in the presence of anhydrous aluminum chloride. The reactants react vigorously together, even at a temperature of about 10 C., as is evidenced'by a rise in temperature in the reaction mass and the evolution therefrom of large amounts of hydrogen chloride. As ordinarily carried out, the chlorinated hydrocarbon mixture is added slowly by increments to the mixture of aromatic hydrocarbon and aluminum chloride, and at the end of the addition or within 5 or 10 minutes thereafter the development of heat in the reaction mass and the evolution of large amounts of hydrogen chloride ceases. The reaction is then apparently complete. This takes a short time, usually less than one hour. Under these conditions the reaction appears to rapidly produce a maximum yield of monoalkyl aromatic compounds as measured by the yield of monoalkyl aromatic sulfonates obtainable by sulfonating Fraction #2 of the resulting condensation mass. It has now been found that when the condensa tion reaction mixture, after apparent completion of the reaction as shown by the substantial cessation of the evolution of heat and large amounts of hydrogen chloride, is stirred for a considerable period of time at an elevated temperature, the reaction apparently continues. The quality of the sulfonated alkyl aromatic compounds resulting from the procedure of the present invention is substantially better than the quality of the sulfonated alkyl aromatic compounds of the usual short condensation period.

In the practice of the invention, the heating of the reaction mixture, after apparent completion of the condensation is carried out for at least 4 one hour at between 50 and 130 C., and pararyl aliphatic compounds containing two or more aryl substituents for each alkane molecule.

Fraction #4.--A comparatively small amount of undistillable residue of pitch-like character.

According to the present invention it has been found that the quality of the crude product as well as the separate Fractions #2 and #3 above described are favorably influenced to an important degree by the temperature and duration of V the condensation reaction. Thus, in accordance with the present invention, it has been found that if the condensation reaction between the aromatic hydrocarbon and the halogenated hydrocarbon mixture of mineral origin is'continued for a substantial length of time beyond the time when the reaction is apparently complete, there is an unexpected and substantial improvement in the properties of Fractions #2 and #3., above. Thus, when the condensation reaction is intensified by keeping the reacting materials in reacting contact at a temperature within the range to 130 C. for a prolonged time period after the con-' densation reaction is apparently complete, it has been found that the crude product remaining after removal of Fraction #1, and Fraction #2 derived therefrom, have unexpected and very desirable properties which are evidenced by the improved characteristics of the detergent mixtures derived from them; and the derived Fraction #3 is a valuable agent for improving lubricants.

ticularly to 90 C. When this is done, changes take place in the condensation mass, as evidenced by improved properties of the crude product and of Fractions #2 and #3 obtained from such crude product, as well as by a notable decrease in the chlorine content of the crude product after tar separation. An advantageous period of heating has been found to be from about 1 to about 8 hours, and preferably from 1 to 5 hours.

When the condensation is carried out at tem peratures below 50 C., the condensation reaction mixture, after apparent completion of the condensation reaction, is heated to the higher temperature and maintained for the prolonged heating period of an houror longer. If desired, however, the condensation may be carried out at temperatures above 50 C. in which case the prolonged heating may be carried out after substan tial completion of the condensation reaction (which usually requires a very short time at such temperatures) at the same or higher tempera matic sulfonate products obtained upon sulfonation of higher alkyl aromatic compounds produced by a process including the prolonged heating at an elevated temperature of the present invention, as compared with similar products made by a similar process, but without the prolonged heating at an elevated temperature.

Another advantage is the superior behavior of the condensation product upon further treatment. Ordinarily, during distillation of the crude c'ondensation product (after separation of the tar layer), hydrogen chloride gas is evolved in substantial amounts as the distillation approaches the end of Fraction #2. This evolved hydrogen chloride is objectionable, not only because 01- its corrosive effect on the equipment, but because the distillation is usually carried out under subatmospheric pressure .and the evolution of the hydrogen chloride makes it difficult to maintain such subatmospheric pressure. The hydrogen chloride is apparently evolved from the decomposition of appreciable amounts of unstable chlorine-containing organic compounds of indefinite composition. One of the advantages of the present invention lies in the much smaller amount of hydrogen chloride evolved on distillation of the product of the prolonged heating treatment, apparently due to the presence of smaller quantitles of unstable chlorine-containing substances. As a result, the crude product can be distilled with much less corrosion of the equipment and with a much more easily maintained vacuum in the still.

An additional advantage'of .the present invention lies in the stability of aqueous solutions of the sultonated higher alkyl aromatic compounds produced in accordance with the present invention when stored for considerable periods of time. In the past, mixtures of sulfonated alkyl aromatic compounds obtained by the suli'onatlon of Frac: tion #2 from an ordinary condensation reaction formed aqueous solutions which, on prolonged storage, showed a gradual decrease in pH, indicating acid-forming decomposition of constituents of the sulfonated products. This acid-forming tendency is particularly objectionable in alkyl aromatic sulionate solutions which are prepared, sold and used as liquid cleaning preparations. It has been found that as a result of the process of the present invention alkyl aromatic sulionates derived from a condensation product which has been prepared by the prolonged condensation treatment of the present invention are comparatively free from instability in aqueous'solutions and may be stored for long periods of time without appreciable change in the pH value of such solutions.

In order that the invention may be understood more fully reference should be had to the following examples and the accompanying drawing in which the figure is an elevation partly in section of one form of apparatus for carrying out the chlorination of the petroleum hydrocarbons.

For convenience, where a kerosene fraction of petroleum is used in the processes disclosed in the examples, the product obtained by chlorinating this fraction is termed keryl chloride and the product obtained bycondensing the keryl chloride with benzene, for example, is termed keryl" benzene. It will be understood that the specific character of the keryl chlorides and keryl" benzenes or other keryP' 'aryl products will be dependent upon the particular kerosene used and the manner in which the process is carried out. Where the parts are indicated, they are by weight and temperatures are in degrees centigrade.

Example 1, part 1.Pennsylva nia kerosene having a boiling range of 189 to 277 and a specific gravity oi. 0.7875 at 24 was chlorinated by .the following procedure: 2500 grams oi. kerosene were placed in a glass flask exposed to difiused daylight. The kerosene was agitated and warmed to 70 to 72. A stream of chlorine Gas was then run into the agitated kerosene, while the temperature of the reacting mixture was held at 70 to 72. The rate of flow of the stream of chlorine gas was about 8 grams per minute. After about 2 hours and 25 minutes,'the stream of chlorine gas was discontinued and a current of air passed through the chlorinated'hydrocarbon mixture to remove dissolved chlorine and hydrogen chloride. The chlorinated hydrocarbon mixture so obtained had a specific gravity increase of about 0.1285 over the original hydrocarbon. The' gain in weight due to organically combined chlorine was 537 grams.

Part 2.-Portions of chlorinated kerosene were condensed with benzene according to two' difierent procedures. Procedure A is an improved, modified condensation process fllustrative of the present invention. Procedure B is a condensation process not embodying the improvements of this invention. a

' PROCEDURE A To an agitated mixture'of 608 grams of benacne and 15.2 grams of anhydrous granular aluminum chloride in a glass vessel, 304 grams of the kerosene chloride prepared as described in part 1 of this example were run in at about 24 during the course of 20 minutes. About five minutes after all of the kerosene chloride had been added the vigorous evolution of hydrogen chloride ceased. The reaction mixture was then heated to reflux (about 85) and agitated and refluxed slowly for about 6 hours. mixture was then poured into a large separatory funnel and allowed to stand for about 16 hours. The reaction mass separated into two layers. The lower tarry layer was withdrawn and discarded. The upper layer which comprised the keryl benzene condensation product was submitted to fractional disillation, first at atmospheric pressure to remove unreacted benzene and then at subatmospheric pressure to effect separation of a fraction consisting largely of keryl benzene,

This keryl benzene fraction boiled between 100 and 235 at 5 mm. of mercury absolute pressure.

PROCEDURE B To an agitated mixture of 608 grams of benzene and 15.2 grams of anhydrous granular aluminum chloride in a glass flask, 304 grams of the kerosene chloride prepared as described in Part 1 of I this example were run in at about 24 during the,

' was withdrawn and discarded. The upper layer lows:

which comprised the keryl benzene condensation product was submitted to fractional distillation, first at atmospheric pressure to remove unreacted benzene and then at subatmospheric pressure to efl'ect separation of a fraction consisting largely of keryl benzene. This keryl benzene fraction boiled between and 235 at 5 mm. of mercury absolute pressure.

Part 3.-A portion of each of the keryl benzene fractions prepared by Procedures A and B of Part 2 of this example were sulfonated at fol- 0 100 grams of the keryl benzen'e fraction were agitated at room temperature for 45 minutes with 10 cc. of 100 per cent sulfuric acid. After allowing to stand for a half hour, the spent acid layer The reaction was withdrawnand discarded. The refined keryl benzene was then agitated at 55 to 60 for one hour with 140 grams of 100 per cent sulfuric acid. The sulfonation reaction mixture was. then allowed to stratify for one hour. Two layers formed. The lower layer consisting almost entirely of spent sulfuric acid was withdrawn and discarded. The upper layer was diluted with about .00 cc. of water and neutralized with 50 per cent caustic soda solution, care being taken to keep the temperature below 45.

The two solutions so prepared from the two keryl benzenes produced according to Procedures A and B were analyzed and sufficient anhydrous sodium sulfate added to each solution to adjust the inorganic salt content of the solute to about 60 per cent. The two solutions were then dried separately by identica1 procedure on a double drum drier. Two light-colored, flaky products having excellent detergent properties were obtained. Thetwo products were tested for odor by dissolving a 5-gram sample in 100 cc. of hot (about 98) water in a 600 cc. tall form beaker and smelling the steam arising from the solution. It was found that the detergent product prepared from the keryl benzene made by Procedure A was noticeabl less odorous than the detergent product prepared from thefkeryl benzene made by Procedure B. 7

Example 2.Pennsylvania kerosene (having a boiling range of 185 to 275 and a specific gravity of 0.790 at 24") was chlorinated by the following procedure. The kerosene was warmed to 45 and an amount of iodine equivalent to 0.04 per cent of its weight was dissolved therein. A stream of chlorine gas was then run into the agitated kerosene, while the temperature of the reacting mixture was held at 55 to 60 by suitable cooling. After the specific'gravity had increased to 0.920 at 24, the chlorination was con-' sidered finished. This corresponded to an increase in weight due to organically combined chlorine of about 21 per cent.

To an agitated mixture of 88 grams of benzene and 9 grams of anhydrous aluminum chloride in a glass vessel, 150 grams of the above-described kerosene chloride were run in, and the resulting liquid mass was agitated for threequarters of an hour at room temperature, when the evolution of hydrogen chloride apparently ceased. The agitated mass was then successively warmed to 30 and held there for one hour, transferred to a separatory funnel and allowed to stand for two hours. The tar, which separated from the standing reaction mass was drawn off, and the remaining non-tarry oil was heated to about 70 at 10 mm. .absolute pressure to strip from it uncondensed excess benzene. The remaining, stripped distilland was a light colored oil.

The oil comprised a large proportion of mono keryl benzene, some poly keryl benzene and poly phenyl alkanes. The oil was sulfonated by placing a 75 gram sample thereof in a glass flask, cooling it to 0 to a'nd'adding slowly to the agitated oil 88.4 grams of 26 per cent oleum, but

tralizing'mass rise above 35. The neutral lightcolored aqueous solution-so obtained was drum dried to yield a light-colored product having excellent detergent properties.

In comparison with a detergent mixture derived from an ordinary condensation, the product of an improved condensation as illustrated in this .example, is more stable during storage as an aqueous,- neutral solution.

Emample 3.A continuous stream of Pennsylvania kerosene (boiling range 185 to 275, specific gravity 0.792) was chlorinated by contactinc it with a stream of chlorine in a reaction zone and continuously removing and cooling the chlorinated kerosene. The apparatus used is shown diagrammatically in the figure.

The apparatus consisted of a glass reaction vessel I having an inlet 2 for the hydrocarbon mixture and an outlet 3 for the chlorination products and by-product hydrogen chloride. Positioned within the vessel I was a chlorine diffuser 4 consisting of a porous alundum cup 5 connected at one end with a duct 6 leading from a supply of chlorine gas (not shown) and closed at the other end by a glass disc 1. For control ling the chlorination temperature, the vessel I was enclosed in temperature controlling jacket 8. When starting the chlorination, the reactor may be warmed-either by passing Warm air through the jacket 8'or by the heat of chlorination. If the latter-method is used, the product obtained before -the reactor temperature has reached the desired value is discarded.

In the operations of the apparatus, kerosene was introduced through inlet 2 and chlorine was introduced through duct 6, under controlled rates of flow. The chlorine was forced through the diffuser 4 in finely dispersed form into intimate contact with the kerosene. The stream of kerosene was spread out into a film between the outer wall of the diifuser 4 and the inner wall of the vessel I, so that it reacted rapidly with the chlorine, forming chlorinated kerosene and hydrogen chloride which were drawn off through outlet 3 to a cooler and separator (not shown). The temperature of the reaction products was taken by a. thermometer in outlet 3 (not shown). The rate of kerosene flow was 11.5 ccs. 'per minute and the rate of chlorine flow about 5 grams per minute. The temperature of the products coming from the reaction zone was about 135. The chlorinated kerosene, after being washed with dilute caustic to remove dissolved chlorine gas and hydrogen chloride therefrom, had a specific gravity of 0.923 and contained 18.7 per cent chlorine. When found necessary to start this continuous chlorination, the reactor was warmed by passing warm'air through the jacket 8, but generally such heating was unnecessary, for the heat of chlorination soon raised the reacting zone to the desired operating temperature, the product obtained before the desired reactor temperature had been rached being separately collected. It was not necessary to preheat either the kerosene or the chlorine, both of which were fed into the apparatus at room temperature. An opaque asbestosshield (not shown) was used to exclude light from the reactor during chlorination.

To a mixture of 2 kilograms of benzene and 50 grams of anhydrous aluminum chloride agitated-briskly in a five-liter flask, one kilogram of the resulting chlorinated kerosene was added at room temperature during the course of a half hour. A cc. sample of the reaction mixture was removed as Sample 1. The tembined chlorine therein.

perature of the mixturewas then raised to 45 in 10 minutes and another 100 cc. was

taken as Sample 2. The batch was kept at 44,

Temperature of the remainder was then raised to 85 in 10 minutes and another 100 ccpwas taken as Sample 6. The batch was then held at 85 to 87 and 100 cc. samples, as Samples '7, 8, and 9, respectively, were taken. During the entire reaction period, the batch .was agitated uninterruptedly.

Immediately after taking the samples, the samples and the remaining condensation mass were each cooled to room temperature and held in separatory funnels without being further agitated, forabout 16- hours, and tar which separated from them was drawn off and discarded. The samples were then washed twice with dilute hydrochloric acid and twice with dilute caustic soda solution. They were then evaporated to constant weight on a. steam bath, and the chlorine content of each of the residual dry samples was determined, using the Parr bomb method. The results obtained are tabulated in the table:

TABLE Chlorine content of'condensation products Chlorine content of Sam le reac on mi:-

N Sample taken after ture after tar separation, per cent 1 Immediately after running in chlorinated kerosene 4. Heating to 45 in minutes. 3. Heating at 4446 for 96 hour. 2. Heating at 44-46 for 1 hour 2. Heating at 4446 for 1% hours 2. Raising temperature to 85 in 10 minutes 1. Heating at 85-87 for 1 hour 1. Heating at 85-87 ior 2 hours 1. Heating at 8587 for 3 hours 0.

Example 4, part 1.-A Pennsylvania petroleum distillate (kerosene) which distills from about 200 to about 266, and of which about 80 per cent distills over the range of about 220 to 260, and which comprises substantially a mixture of hydrocarbons which are chiefly aliphatic and saturated, is chlorinated at about 50 bypassing through it a stream of chlorine gas until the chlorinated mixture has increased in weight by about per cent because of organically-com- The resulting mixture of unchlorinated and chlorinated hydrocarbons is aerated to remove"practically all dissolved hydrogen chloride. 30 parts of anhydrous aluminum chloride are added slowly toan agitated mixture of 200 parts of benzol and 300, parts of the chlorinated kerosene, containing chlorinated and unchlorinated hydrocarbons. The mixture is cooled externally until the vigorous evolution cury pressure is collected and consists oi a mixture oi, alkylated benzenes in which the alml groups predominantly contain from about 12 to about 15 carbon atoms. The resulting mixture is a light amber-colored, somewhat oily, but not viscuous, liquid which is insoluble in water, but soluble in the common organic solvents.

Part 2.-l00 .parts of the distilled oil obtained according to Part 1 of this example are mixed with 130 parts of 20 per cent oleum at a temperature of approximately 10. The mixture isallowed to warm to 25 to 30 and is-stirred at this temperature for 1 /2 to 3 hours or until one part of a test portion, after neutralizing with sodium hydroxide, s soluble in 20 parts or water. The mixture is then poured into approximately 600 parts of an ice-water mixture, and the resulting solution is made neutral to Brilliant Yellow and Congo red papers with caustic alkali (e. g., sodium hydroxide). The neutralized solution is evaporated to dryness on a rotary drumdrier. The product obtained isin the form of lightbufl. to white flakes. It comprises chiefly a mixture 01' alkyl benzene sulfonates and alkali metal sulfate. Aqueous solutions of th product have excellent washing properties, as well as good wetting, insecticidal, and fungicidal properties.

Example 5, part 1.300 parts of the chlorinated kerosene employed in Example 4 are mixed with 30 parts of anhydrous aluminum chloride and 150 parts of commercial diphenyl. The mixture is agitated under reflux at room temperature (that is, at about 15 to 30) for about one hour and thereafter at about 75 for about one and a half hours. The mass is then cooled to about 20 to 30 and poured into a mixture of 600 parts of ice water and 30 parts of commercial muriatic acid. The aluminum salts dissolve in thecold dilute acid while the organic matter which contains the alkylated diphenyl compounds is precipitated in a semi-liquid, pastyform. Small amounts of benzene and/or ether are added to the agitated aqueous mixture to dissolve the organic products. Upon standing, the mixture separatesinto an upper layer which is a solution of the organic matter in the organic solvent, and

a lower aqueous acid layer which is withdrawn and discarded. The benzol and/or ether solution or organic matter is washed with wate until it i reasonably free of acid, and is then distilled in vacuo. The fraction of the distillate which boils at about 170 to about, 260 at 5 mm. pressure is of hydrogen chloride gases from the mixture has abated. It is then heated and maintained at its refluxing temperature for about one hour; or until the evolution of hydrogen chloride has ceased.

' from about 160 to about 210 at 4 mm. of mercollected separately. It is a light-yellow viscous oil which is insoluble in water, but soluble in benzene and in ether. It is a mixture comprised chiefly of alkylated diphenyl compounds in which the alkyl groups correspond with the kerosene hydrocarbons employed. It may also contain some chlor-alkyl diphenyl compounds derived from the dichlor hydrocarbons.

Part 2. 25 parts of the oil obtained according to Part lot this example, are mixed with 15 parts or 100 percent sulfuric acid and stirred at about for about 20 minutes, or until a 1 cc. sample ispractically completely soluble in about 10 cos. of water at about 25. The sulfonation mass is poured into 300 parts of water and the aqueous acid mixture is neutralized with caustic alkali or a water-soluble carbonate (e. g., sodium carbonate), and the resulting neutral solution is dried. The product. ischiefly a, mixture of the salts (e. g., alkali metal salts) of alkyl-diphenyl sulfonic acids. It is a light-brown to white solid which is soluble in water, and in aqueous solutions 01' mineral acids and of water-soluble alkalies.

- oil.

Zeilicient detergent adjusted to 17.5 cc. per minute.

Example 6.The petroleum fraction used in this example is known commerciallyas white 278 and more than 85 per cent distills over the range 195 to 260. For convenience, the condensation products from white oil and benzene are called "white-oil-benzene compounds.

2270 lbs. of white oil were agitated in a vessel lined with lead. 1.75 lbs. of iodine were dissolved in the agitated white oil. Chlorine gas was then passed through the oil with continued agitation until 'the speciflcgravity of the sample showed an increase of 0.09 over that of the original white During chlorination, the temperature was adjusted to 70 to 86 by suitably'heating or cooling the batch.- The chlorinated white oil weighed approximately 2651 lbs. The degree of chlorination corresponded to about 150% chlorination.

617 lbs. of benzene and .62 lbs. of anhydrous aluminum chloride were agitated in an Alleghany metal kettle, warmed to to and held at that temperature for about an hour and a quarter during which period 617 lbs. of the chlorinated white oil (prepared as above described) were run in. The agitated mixture was then warmed to 55 and agitated at 55 to 59 for an hour. The agitation was then stopped and the batch was allowed to settle for about 18 hours. During this period, the batch was allowed to cool down to about 30. Some 248 lbs. of tar which settled out were discarded.

The crude condensation product was trans-,

ferred to a stripping kettle, and unreacted benzene was stripped oil by gradually heating the batch to 150 and holding it at that temperature until distillation ceased and then simultaneously increasing the vacuum in the still to approximately 27 inches of mercury and gradually heating the distilland to about 175. The remaining stripped white-oil-benzene weighed 433 lbs.

200- lbs. of stripped white-oil-benzene were charged into an enamel-lined kettle fitted with an enameled agitator'and other suitable acces-..

sories. The batch was then cooled to 16 and 266 lbs. of 100 per cent sulfuric acid were run in during an hour and a quarter. The temperature was then raised to to and held there for about an hour and a half. 120 lbs. of water were then added slowly to the batch, which was cooled so that the final and highest temperature thereof was 66. To the mixture, 80 lbs. of Stoddard solvent were added. After agitating the batch for 15 minutes, and then allowing it to stand for one hour, the lower spent acid layer was drawn off. Then 80 lbs. more of Stoddard solvent were added to the batch which was agitated for 15 minutes and allowed to stand for about 18 hours before the rest of the spent acid was drawn off.

The sulfonation mixture was then neutralized with 50 per cent aqueous caustic soda solution. The resulting product, which was a solution of white-oil-benzene-sodium-sulfonate in Stoddard solvent," was adapted for use in preparing highly compositions for dry cleaning.

f Example 7.-White oil of the type employed in Example 6 was used in this'example. The white lpreheated to 90 by a suitable device was inoduced into the chlorinator shown in the figure rough tube 2. The rate of flow of white oil was The flow of chlorine gas through inlet tube 6 wa at the rate of about 5 grams per minute. The temperature to rise to 175 to 180. After a stable state of conditionswas attained, 500 grams of-chlorinated product having a specific gravity of 0.927 at 24 were collected and condensed with benzene as follows:

500 grams of chlorinated white oil prepared as described above were run into an agitated mixture of 500 grams of benzene and 50 grams of aluminum chloride, which mixture wa kept at The addition of the white oil chloride was made over a period of about 20 minutes. After all the white oil chloride had been run in, the reaction mixture was agitated at to forabout 3 hours. thenallowed .to stand to stratify. The mixture separated into two layers. The lower-tarry layer was drawn on and discarded. The upper layer was distilled, first at atmospheric pressure to a vapor temperature of and then at 15 millimeters of mercury absolute pressure to a vapor temperature of 90 to remove unreacted benzene. The hot residue was agitated for several minutes with Tonsil clay (an activated clay) and filtered.

The oily condensation product so obtained weighed 376 grams.

200 grams of the oily condensation product prepared as described above were agitated and 200 cc. of 100 per cent sulfuric acid were added at room temperature during the course of 10 minutes. The reaction mixture was then warmed to 55 to 60 and agitated for 1 hour. After cooling to room temperature, cc. of cold water were added with agitation and cooling, care being taken to keep the temperature below 45.

300 cc. of Sovasol (Socony-Vacuum brand of Stoddard solvent) were then added,' the mixture and was useful for preparing dry cleaning pastes.-

having outstandingly excellent detergent properties.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative examples and that changes can be made without departing from the scope of the invention.

The hydrocarbon mixtures which may be employed as starting materials in accordance with the present invention are non-aromatic hydrocarbon mixtures, preferably aliphatic hydrocarbon mixtures, and especially mineral oil distillates, containing between 7 and 35 carbon atoms. and preferably kerosene fractions of such distillates containing an average of 10 to 16 carbon atoms. The particular type of hydrocarbon mixture employed will vary, depending upon the specific use for which the product is designed and the particular aromatic nucleus with which it is combined, as will be evident to those acquainted with the art. (By the term non-aromatic hydrocarbon mixtures as employed herein, I mean hydrocarbon mixtures containing essentially straight and/or branched open chain saturated hydrocarbons and/or alicyclic hydrocarbons and which may contain other hydrocarbons but preferably not more than 20 per cent of aryl hydrocarbons, such as petroleum, petroleum distillates,

artificially or syntheticallyprepared mixtures,

The reaction mixture was lates are mainly mixtures of aliphatic hydrocarbons, including both saturated acyclic aliphatic hydrocarbons containing straight or branched carbon chains and cyclic aliphatic hydrocarbons,

as well as some aromatic hydrocarbons and some unsaturated aliphatic hydrocarbons, depending upon the source of the petroleum and the method of distillation and/or purification. When the petroleum distillates are halogenated in-the preparation of products of the present invention, mix- 10 'tures of various halogenated derivatives of the said aliphatic hydrocarbons (alkyl halides) are produced and the said mixtures of alkyl halides, when condensed with aromatic hydrocarbons,

produce mixtures of alkyl aromatic compounds,

in which the alkyl groups correspond with ali-" phatic hydrocarbons of the petroleum distillate from which they were produced. Accordingly, when the mixtures of allgvl aromatic compounds are sulfonated, compositions are produced which contain mixtures of sulfonated alkyl aromatic compounds differing from each other in the alkyl groups, which groupscorrespond with the aliphatic hydrocarbons of the mixtures employed.

The preferred hydrocarbon mixtures employed in accordance with the present invention are exemplified by fractions of Pennsylvania and Michigan (Mount Pleasant) petroleum distillates. These distillates consist essentially of open chain aliphatic (parafllnic) hydrocarbons a large portion of which are probably relatively long carbon chains rather than more condensed molecules. Such distillates are referred to herein as of the Pennsylvania type. By this term it is intended to include not only straight run distillates derived from petroleums of the-type mentioned above, but also processed petroleum hydrocarbons derived from less desirable petroleum distillates, such as petroleum distillates which have been treated by one of the various solvent processes.

Generally, the petroleum distillate contains a substantial amount of aryl hydrocarbons, preferably not more than 20 per cent. It has been found that the advantages of the present invention are particularly apparent when the petro leum distillate used contains a substantial amount of aryl hydrocarbons.

The chlorination of'the complex hydrocarbon mixture is carried out to such an extent that the resulting chlorination reaction mixture contains an amount of organically combined chlorine which corresponds to from '75 to 200 per cent, more particularly 100 to 1'75 per cent, and preferably 110 to 150 per cent, of the theoretical amount of chlorine which would be present if all of the original alkyl hydrocarbons'in the mixture were monochlorinated (termed in the claims "percent of theoretical monochlorination"). Preferably, the chlorinated products are employed, but other corresponding halogenated hydrocarbon mixtures may be used in place of chlorinated mixtures.

Any of several known methods of chlorination may be used. Thus, the chlorination may be carried out in batches by passing chlorine gas into an agitated charge of petroleum distillate such as kerosene, or by a continuous chlorination process such as. that illustrated in Examples 6 ,and 7, above. The present invention is of particular advantage in connection with the condensation of aromatic hydrocarbons with mixtures of chlorinated complex alkyl hydrocarbon mixtures of mineral origin produced by such a continuous chlorination procedure.

In general, the halogenation of the petroleum distillate may be stimulated by the presence of halogenating catalysts such as iodine, phosphorus trichloride, or actinic light./ Chlorination may be carried out at various temperatures such as from 0 to 200 C. For ordinary batch operation, where chlorine is slowly run into a batch of the petroleum distillate a temperature of about 60 to 70 C. is desirable.

The proportion of aromatic hydrocarbon to halogenated petroleum distillate may be varied. Theoretically, in order to obtain complete reaction, one moi of aromatic material must be used per atom of chlorine combined with the petroleum hydrocarbon fraction; in practice, a large excess, preferably about twice the weight of aromatic hydrocarbon as the weight of halogenated petroleum distillate is used, as this favors complete reaction and permits less decomposition and leum distillate employed with respect to the amount of aromatic hydrocarbon used in the preparation of the alkylated aromatic compounds.

The improved results of the present invention are best effected by a condensation of the halogenated hydrocarbon mixture and aromatic hydrocarbon with the aid of an amount of anhydrous aluminum chloride which is from 1 to 8 per cent of the weight of the halbgenated hydrocarbon mixture, and particularly from 2 to 5 per cent. In general, with amounts less than 2 per cent, condensation is retarded; while I with amounts larger than 5 per cent, there is no marked increase in the rate of condensation, though the quality of condensed product is improved, while the yield is somewhat decreased. While Friedel and Crafts condensing agents other than aluminum chloride may be employed, aluminum chloride is preferred for the condensation of an aromatic hydrocarbon with a halogenated hydrocarbon mixture of the type of a. petroleum distillate in view of its superior action.

The sulfonation of the mixture of alkyl aromatic compounds is effected with sulfuric acid of various strengths such as 66 B., 100 per cent, 26 per cent, and 65 per cent oleum. Preferably. the sulfonation is eifected with 98 to 100 per cent sulfuric acid or with oleum containing up to 10 per cent S03; the use of these sulfonating agents produces better yields and lesser discoloration of product than other sulfonating agents. The sulfonation may be carried out in the presence of inert solvents or diluents, and sulfonation as-' sistants as, for example, the lower fatteyacids' such as sodium or potassium sulfate, may be employed, Also, the temperature at which the sulfonation is carried out may vary within wide limits. For example, temperatures as low as about 0 C. and-as high as about'140 C. may be employed. In general, the more vigorou the sulfonating agent the lower is the Preferred temperature. In general, the sulfonation is preferably carried out at temperatures between 5 and C. For complete sulfonation the sulfonating agent in terms of per cent sulfuric acid may be employed in amounts which range from 0.3 to 5 times or more the weight of the condensation product to be sulfonated. Ordinarily, the extent to which the sulfonation is carried out will vary with the individual material being sulionated, the duration of the suli'onation. and the use to be made of the sulfonated product.

This application is a continuation-in-part 01" my applications Serial No. 93,521, filed July 30, 1936, now Patent No. 2,283,199 and Serial No. 400,334, filed June 28, 1941.

' I claim:

1. In a method of producing sulfonated higher alkyl derivatives of aromatic hydrocarbons which comprises heating at a condensation temperature a reaction mixture containing an arc atic hydrocarbon having not more than two benzene nuclei, a Friedel and Crafts condensing agent, and a halogenated hydrocarbon mixture derived from a complex hydrocarbon mixture of mineral origin containing an average of 10 to 16 carbon atoms per molecule, said halogenated hydrocarbon mixture containing an amount of halogen tion product, the improvement which comprises heating the condensation reaction mixture at a temperature between 70 and 130 C. for at least one hour after the evolution of hydrogen halide has substantially ceased.

'2. In a method of producing sulionated higher alkyl derivatives of aromatic hydrocarbons which comprises heating at a condensation temperature a reaction mixture containing an aromatic hydrocarbon having not more than two benzene nuclei, aluminum chloride as a condensing agent, and a chlorinated hydrocarbon mixture derived from a complex hydrocarbon mixture of mineral origin containing an average of 10 to 16 carbon atoms per molecule, said chlorinated hydrocarbon mixture containing an amount of chlorine correspondingto 100% to 175% of theoretical monochlorination, and sulfonating the condensation product, the improvement which comprises heating the condensation reaction mixture at a temperature between 70 and 90 C. for at least one 'hour after the evolution of hydrogen chloride has tial amount of aryl hydrocarbons, and sulfonat-,

ing the condensation product, the improvement which comprises mixing the aluminum chloridewith the aromatic hydrocarbon, gradually adding th chlorinated hydrocarbon mixture thereto,

and heating the condensation reaction mixture at a temperature between 70 and 130 C. for at least one hour after the evolution 01' hydrogen chloride has substantially ceased.

4. In a method of producing sulfonated alkyl aromatic hydrocarbons which comprises heating at a condensation temperature a reaction mixture containing a mononuclear aromatic hydrocarbon, a chlorinated kerosene fraction of petroleum distillate containing an amount of chlorine corresponding to 75% to 200% of theoretical monochlorination, and aluminum chloride as a condensing agent, fractionating the crude condensation product, and sulfonating a fraction thereof corresponding to 75% to 200% oi theoretical monohalogenation, and sulfonating the condensa containingprlmarily monoalkyl aromatic compounds, the improvement which comprises continuing the heating of the condensation reaction mixture, containing an amount of the mononuclear aromatic hydrocarbon at least twice the weight 01' the chlorinated kerosene, at a temperature between 70 and 130 C. for 1 to 8 hours after the evolution of hydrogen chloride has substantially ceased.

5. In a method 01' producing sulionated alkyl aromatic hydrocarbons which comprises heating at a condensation temperature a reaction mixture containing benzene, a chlorinated kerosene con taining an amount of chlorine corresponding to 110% to 150% of theoretical monochlorination and obtained by chlorinating a kerosene traction of a petroleum distillate containing a substantial amount of aryl hydrocarbons, and aluminum chloride as a condensing agent, and sulfonating the condensation product, the improvement which comprises continuing the heating or the condensation reaction mixture, containing an amount 01' benzene at least twice the weight oi the chicrinated kerosene, at a temperature of about to about 90 C., for 1 to 8 hours after the evolution oi hydrogen chloride has substantially ceased.

,6. In a method of producing sulfonated alkyl aromatic hydrocarbons which comprises heating at acondensation temperature a reaction mixture containing benzene, a chlorinated kerosene fraction of petroleum distillate containing an amount of chlorine corresponding to to 200% of theoretical monochlorination, and aluminum chloride as a condensing agent, fractionatin the crude condensation product, and sulfonating a fraction thereof containing primarily monoalkyi [aromatic compounds, the improvement which comprises mixing the aluminum chloride with the benzene,gradually adding the chlorinated kerosene fraction thereto, heating the reaction mixture at a condensation temperature, and further heating the reaction mass at a temperature of 70 to'about C. for 1 to 8 hours after the evolutionof hydrogen chloride has substantially ceased.

LAWRENCE H. FLETT. 

